CVE-2019-0995 — Internet Explorer Security Feature Bypass Vulnerability

Executive Summary

A security feature bypass vulnerability exists when urlmon.dll improperly handles certain Mark of the Web queries. The vulnerability allows Internet Explorer to bypass Mark of the Web warnings or restrictions for files downloaded or created in a specific way. In a web-based attack scenario, an attacker would need to host a malicious file that is designed to exploit the vulnerability and then convince a user to download the malicious file and then open the file in Internet Explorer. The security update addresses the vulnerability by modifying how urlmon.dll handles Mark of the Web queries.

Overview

7.3

CVSS HIGH

Important

MS Severity

Not Exploited

MS Exploit Status

Less Likely

MS Exploit Likelihood

Category Security Feature Bypass

Released May 14 2019

Last Updated May 14 2019

Publicly Disclosed No

CISA KEV Not Listed

Known Exploits None Known

EPSS Score 0.04948 — 0.91046 percentile

CVSS Vector

ATTACK VECTOR

Local

ATTACK COMPLEXITY

Low

PRIVILEGES REQUIRED

Low

USER INTERACTION

Required

SCOPE

Unchanged

Temporal Score: 6.6

EPSS Score

0.04948

probability of exploitation in the next 30 days

0.91046 percentile - updated 2026-06-20

View on FIRST.org

Affected Products

18 affected products

Product	KB Article	Severity	Impact	Restart Required
Internet Explorer 11 on Windows 10 Version 1607 for 32-bit Systems	`4494440 (Security Update)`	Important	Security Feature Bypass	Yes
Internet Explorer 11 on Windows 10 Version 1607 for x64-based Systems	`4494440 (Security Update)`	Important	Security Feature Bypass	Yes
Internet Explorer 11 on Windows 10 Version 1703 for 32-bit Systems	`4499181 (Security Update)`	Important	Security Feature Bypass	Yes
Internet Explorer 11 on Windows 10 Version 1703 for x64-based Systems	`4499181 (Security Update)`	Important	Security Feature Bypass	Yes
Internet Explorer 11 on Windows 10 Version 1709 for 32-bit Systems	`4499179 (Security Update)`	Important	Security Feature Bypass	Yes
Internet Explorer 11 on Windows 10 Version 1709 for ARM64-based Systems	`4499179 (Security Update)`	Important	Security Feature Bypass	Yes
Internet Explorer 11 on Windows 10 Version 1709 for x64-based Systems	`4499179 (Security Update)`	Important	Security Feature Bypass	Yes
Internet Explorer 11 on Windows 10 Version 1803 for 32-bit Systems	`4499167 (Security Update)`	Important	Security Feature Bypass	Yes
Internet Explorer 11 on Windows 10 Version 1803 for ARM64-based Systems	`4499167 (Security Update)`	Important	Security Feature Bypass	Yes
Internet Explorer 11 on Windows 10 Version 1803 for x64-based Systems	`4499167 (Security Update)`	Important	Security Feature Bypass	Yes
Internet Explorer 11 on Windows 10 Version 1809 for 32-bit Systems	`4494441 (Security Update)`	Important	Security Feature Bypass	Yes
Internet Explorer 11 on Windows 10 Version 1809 for ARM64-based Systems	`4494441 (Security Update)`	Important	Security Feature Bypass	Yes
Internet Explorer 11 on Windows 10 Version 1809 for x64-based Systems	`4494441 (Security Update)`	Important	Security Feature Bypass	Yes
Internet Explorer 11 on Windows 10 Version 1903 for 32-bit Systems	`4497936 (Security Update)`	Important	Security Feature Bypass	Yes
Internet Explorer 11 on Windows 10 Version 1903 for ARM64-based Systems	`4497936 (Security Update)`	Important	Security Feature Bypass	Yes
Internet Explorer 11 on Windows 10 Version 1903 for x64-based Systems	`4497936 (Security Update)`	Important	Security Feature Bypass	Yes
Internet Explorer 11 on Windows Server 2016	`4494440 (Security Update)`	Low	Security Feature Bypass	Yes
Internet Explorer 11 on Windows Server 2019	`4494441 (Security Update)`	Low	Security Feature Bypass	Yes

Patches

6 patches

Article	Type	Restart
`4494440`	Security Update	Yes
`4499181`	Security Update	Yes
`4499179`	Security Update	Yes
`4499167`	Security Update	Yes
`4494441`	Security Update	Yes
`4497936`	Security Update	Yes

Known Exploits

No known exploits have been linked for this CVE yet. When available, exploit references will be sourced from public repositories and may be unverified, incomplete, or non-functional. Always review code carefully before use in any environment.

Acknowledgments

John Page aka hyp3rlinx of Apparition Security

References

MSRC Advisory MITRE NVD